Machines for shaping uppers over lasts



Aug- 20, 195 J. c. JORGENSEN MACHINES FOR SHAPING UPPERS OVER LAST-S,

Filed may 9, 1955 2 Sheets-Sheet l In 11 en t or Jacob C Jorgensen J. C. JORGENSEN MACHINES FOR SHAPING UPPERS OVER LASTS 2 Sheets-Sheet 2 Aug. 20, 1957 Filed May 9, 1955 QSJ X MACHINES FDR SHAPING UPPERS @VER LASTS Jacob C. Jorgensen, Wenham, Mass., assignor to United Shoe Machinery Corporation, Flemingten, N. L, a corporation of New Jersey Application May 9, 1955, Serial No. 506,894

18 Claims. (Cl. 12--10.4)

use in pulling over machines or to embodiment in a ma-' chine of the exact mechanical construction shown in the mentioned patent.

For shaping the upper materials of a shoe over a last, pulling over machines as well as certain types of lasting machines are provided with grippers for seizing the upper,

materials in different locations spaced apart around the toe end and forepart of the last and these grippers are operated to exert a pull on the upper materials extending in a direction heightwise of the last for stretching and shaping the upper materials over the last. As the upper materials are thus drawn snugly against the last by the grippers, an ever-increasing frictional resistance is set up between the surface of the last and those portions of the upper materials which are wrapped around the curved sides of the last. Because of this frictional resistance, it becomes very difficult, and in some cases it may be impossible, to exert on the upper materials a pull of suflicient force to stretch those portions of the upper materials which extend across the top part of the last and to draw them snugly down onto the last. With the view of overcoming this difficulty it has been hitherto proposed to oscillate or to vibrate the last mechanically as shown, for example, in United States Letters Patent No. 1,162,378, issued'on November 30, 1915, in the name of Ronald P. McFeely. While prior arrangements of this type have a tendency to alleviate the aforementioned condition to a somewhat limited extent, they fall far short of providing an entirely satisfactory solution to this problem.

It is, therefore, a principal object of this invention to provide a novel and improved machine for shaping uppers over lasts which overcomes the mentioned difiiculty in a relatively simple yet very effective manner. More particularly, it has been discovered that the frictional resistance between the upper materials and a last may be very substantiallyreduced, and for all practical purposes entirely eliminated, if the last is subjected to a rapid series of hammer blows, or percussive impulses, during the operation of the grippers to stretch and to shape the upper over the last. While the actual phenomenon produced by thus subjecting the last to a rapid series of hammer blows, or percussive impulses is not wholly understood, it does appear that the last itself is rendered alive in a manner which reduces or eliminates the frictional resistance between the last and the upper materials and thus renders the pull applied by the grippers entirely effective for stretching and shaping the upper to the last. In any event, it has been definitely established by actual tests that the aforementioned desirable results are obtained.

Hence, in accordance with a feature of this invention,

the herein illustrated machine, which has the usual arrangement of toe and side grippers for seizing and pulling the upper materials of a shoe over a last, together with a shoe rest for supporting the last during the action of the grippers, is also provided with a member movable relatively to the shoe rest for imparting a rapid series of hammer blows, or percussive impulses, to the last during the operation of the grippers. More particularly, the member for imparting the series of hammer blows, or percussive impulses, comprises a fluid pressure operated piston which may be arranged either to act directly on the bottom of the last, or insole on the last, or alternatively on the shoe rest which supports the last. Preferably, and in the herein illustrated machine, the grippers are actuated by means of fluid pressure operated pistons and the arrangement is such that the grippers exert positive and unyielding pulls on the upper materials of selectively predetermined intensity. Control means are also provided for automatically setting the fluid pressure operated piston into action immediately after the grippers have been operated to exert their pull on the upper materials and for automatically terminating the action of the hammer after a variably predetermined interval. In addition to this automatic control, the herein illustrated machine has a manual control means for operating the piston which the operator may use to subject the last to additional percussive action.

The above and other objects and features of the invention will become apparent in the following detailed description of the preferred embodiment thereof which is illustrated in the accompanying drawings, and will be pointed out in the claims.

In the drawings,

Fig. 1 is a view in perspective of a pulling over machine to which an illustrative embodiment of the invention is applied; 5

Fig. 2 is a view in side elevation of certain portions of the machine shown in Fig. 1, with some parts in vertical section and showing various operating elements thereof somewhat schematically; and

Fig. 3 is a view in section substantially on line IIIIII of Fig. 2, looking in the direction of the arrows.

Referring to these drawings, and particularly to Fig. 1 thereof, the invention is therein illustrated by way of an example as embodied in a pulling over machine of the type disclosed and claimed in Patent No. 2,736,046, mentioned above. This machine is provided with a toe gripper 10 and a pair of side grippers 12, 12 which are actuated by fluid pressure operated pistons to pull the upper of a shoe over its last and with overlaying and fastener inserting devices for wiping the lasting margin of the tensioned upper inwardly over and for securing it to the bottom of the shoe, the overlaying device for the toe end of the shoe being herein identified by the reference character 14, while the two side overlaying devices are identified by the reference characters 16, 16. During the operation of the machine, the shoe is supported on a shoe rest, indicated generally by the reference character 18 and is held against heelward movement by means of a heel rest 20. After the grippers 10, 12, 12 have been closed on the upper materials and have been operated to pull the upper over the last, but before these grippers are opened to release the upper in response to the inward movements of the overlaying and fastener inserting devices 14, 16, 16, the tensioned upper is securely clamped against the opposite sides of the last by means of a pair of side clamps 22, 22.

The toe gripper 10 is arranged to be moved in a direction heightwise of the shoe being pulled over, herein indicated by the reference character S and illustrated as comprising an upper U and an insole I assembled on a last L, after it has been closed to seize the upper at the toe end of the shoe, by fluid pressure operated means in the following manner. At its lower end this gripper is connected to a pair of pivotally mounted arms, the outer end of one of these arms appearing in Fig. 2 and being identified by the reference character 32. Secured to a part of the machine frame 34 is a housing 36 in which there are two cylinder bores 38, one of these bores being directly in back of the other as viewed in Fig. 2 of the drawings. Slidable in each of these bores is a piston 40, one of which is visible in Fig. 2, and each of these pistons is connected to an arm 32 by means of a connecting rod 42 having a slotted upper end 44 which embraces a pin 46 in the associated lever 32. Connected to a cross passage 50, which is in communication with each of the two cylinder bores 38, above the pistons 40 therein, is a conduit 52 through which fluid under pressure from a suitable source, not shown, is admitted to these cylinder bores for operating the pistons at an appropriate time in the operating cycle of the machine. The two side grippers 12, 12 are similarly operated by fluid under pressure for movement in directions extending heightwise of the shoe S after they have been closed to seize the upper at the opposite sides of the toe end of the shoe. Thus each of these grippers is connected at its lower end to a pivoted arm 60, a portion of one of these arms appearing in Fig. 2. Extending downwardly from these arms are two connecting rods 62, 62 which at their lower ends are connected to an equalizing lever 64. This equalizing lever is pivotally mounted on a stem portion 66 which extends downwardly from a piston 68. This piston is slidable within a cylinder bore 70 formed in a housing 72 which is associated with the previously mentioned housing 36. At an appropriate time in the operating cycle of the machine, fluid under pressure is admitted to the cylinder bore 70, above the piston 68, through a passage 69, thereby forcing the piston downwardly and moving the grippers 12, 12 in a direction extending heightwise of the shoe. For further details of the particular type of fluid pressure operated mechanisms actually provided in the prior machine for operating the toe and side grippers, reference may be made to the aforementioned Patent No. 2,736.046. It will be understood, however, that in so far as the present invention is concerned, any other suitable fluid pressure operated mechanism may be utilized for this purpose and, in fact, the advantages of the present invention may be r alized in a machine having grippers which are operated mechanically.

As is the case in pulling over machines in general, the machine to which the present invention is herein shown as applied, is adapted to operate in a cycle of operations having two distinct stages. During the initial stage of the operating cycle, the grippers are first closed on the upper materials and then are moved in a direction extending heightwise of the shoe on the support 18 to apply a pull to the upper materials to stretch them over the last L, the machine then coming to a stop with the upper held under tension by the grippers. After making certain adjusting movements of the upper relatively to the last by suitable manipulation of the toe, and/ or side grippers, the operator again starts the machine and the second stage of its operating cycle, in the course of which the overlaying and fastener inserting devices are operated to wipe the lasting margin of the tensioned upper in over and to secure it to the bottom of the shoe, is completed. It is during the initial stage of the operating cycle that the upper U is shaped to the last and the present invention is directed to the improvement of the operation of the machine with respect to the shaping of the upper to the last in response to the pull applied thereto by the grippers. For this purpose, the herein illustrated machine is provided with fluid pressure operated means for imparting to the last a rapid series of hammer blows, or percussive impulses while the upper is subjected to a tensioning pull by the grippers. In the specific embodiment illustrated in the drawings, this means comprises a piston having a head 82 of reduced diameter and slidable within a cylindrical bore 84 formed in a housing member 86 which is supported in a suitable manner on a portion of the machine frame, not shown, in the location indicated in Fig. 2 of the drawings. The shoe rest 18 includes a centrally located member 88 carrying at its outer end a foot 90 which is in direct engagement with the insole I of the shoe S, and two side members 92, 92 which are also in engagement with the insole. The piston 80 is directly in line with the member 88 so that when this piston is projected upwardly and to the right as viewed in Fig. 2, see also Fig. 3, it will strike the member 88 a blow the force of which will be transmitted directly to the last L. For operating this piston in a manner to impart a rapid series of pressure impulses, or hammer blows to the last, the following arrangement is provided.

The cylindrical bore 84 is connected by means of a pressure hose to one end of a housing 102 provided with a cylindrical bore 104 in which there is slidably mounted a piston 106. As is illustrated in Fig. 1 of the drawings, the housing 102 is mounted directly on a side wall of a portion of the frame 34 of the pulling over machine. Movement of the piston 80 downwardly into the bore 84 is limited by a shoulder 108, while downward movement of the piston 106 in the bore 104 is limited by a shoulder nut 110 threaded into the housing 102. The space beneath the piston 80 in the bore 84, the pressure hose 100 and the space in the bore 104 above the piston 106 are entirely filled with some incompressible liquid such, for example, as oil. Connected to the piston 106 is a link member 112 the lower portion of which is provided with a cylindrical bore 114 and also with a transverse slot 116. Located within this slot is the central portion of a lever 118 which is pivotally supported at one end on a stud 120, mounted in the frame of the machine, see Fig. 1. At its other end, this lever carries a roll 122 which is held against the periphery of a cam 124 by means of a coil spring 126. Extending across the slot 116 in the link member 112 and passing through an elongated slot 125 in the lever 118 is a pin 127 which is secured at its opposite ends in the lower portion of the link 112. The cam 124 is carried on one end of a shaft 130 which is journaled in suitable bearings provided in the frame of the machine and is driven at a relatively high speed from an electric motor 132, which conveniently may be the same motor used for supplying power to the pulling over machine itself, by means of pulleys 134, 136 and a drive belt 138, Fig. 1. Slidably mounted within the bore 114 is a piston 140. Interposed between this piston and the mid portion of the lever 118 is a compression spring 142.

Connected to the bore 114 above the piston 140 is one end of a pressure hose 144 the other end of which is connected to a pipe 146 which leads to a port 148 formed in a valve housing 150 and which has a branch portion 152 leading to a port 154 in a second valve housing 156. Slidably mounted in a bore 157 in the valve housing 150 is a valve member 158 which, when held in the position in which it is shown by means of a coil spring 160, is adapted to connect the port 148 to a port 162 which is in communication with an exhaust duct 164. This valve plunger is adapted to be moved to the right by fluid under pressure admitted to the left-hand end of the bore 157 through a passage 168, and when thus moved to the right, this valve member gradually closes the port 162 and opens up communication between the port 148 and a third port 170. The port is connected to a conduit 172 which leads to a union 174 from which there extend three conduits 176, 178 and 180, the latter of which is connected directly to the previously mentioned conduit 52. The conduit 178 is connected to the passage 168 in which there is interposed a needle valve 182, while the conduit 176 is connected to this passage between the needle valve and the left-hand end of the bore 157, and associated with this conduit is a check valve 184 which opens in the direction indicated by the arrow in Fig. 2. Connected to an intermediate portion of the conduit 172 is a conduit 186 which leads to a port 188 in the valve housing 156. Slidable within a bore 190 in this valve housing is a valve member 192 which, when it is held in the position shown by a spring 193, is adapted to close off communication between the port 188 and the port 154. This valve plunger is connected by means of links 194, 196 and bell-crank levers 198, 200, to a control handle 202, see also Fig. l, by means of which it may be moved to the left to a position in which communication is established between the ports 188 and 154.

When the pulling over machine is in use, the motor 132 runs continuously and the lever 118 will be vibrated at a very rapid rate (approximately 1800 times per minute). However, until fluid under pressure is admitted to the space in the bore 114 above the piston 140, this vibrating motion of the lever 118 is not transmitted to the link 112 or to the piston 106 which is connected thereto. When fluidunder pressure is admitted to the cylinders 38 through the conduit 52, the toe gripper will be operated to exert a pull on the lasting margin of the upper materials and substantially at the same time in the initial stage of the operating cycle of the machine, the side grippers 12, 12 will be similarly operated to apply their pulls on the upper material in response to the admission of fluid under pressure to the cylinder 70. Fluid under pressure from the conduit 52 flows through the conduits 180 and 178 and past the needle valve through the passage 168 into the chamber 157 thereby moving the valve member 158 slowly to the right. As this valve member moves in this direction, the port 170 is gradually opened so that fluid under pressure from the conduit 172 will be admitted through this port to the port 148 and thence through the conduits 146, 144 to the space in the cylinder 114 above the piston 140. At first, and before the port 162 is fully closed, the pressure of the fluid in this space is reduced considerably by the leakage through the port 162. Very soon, however, the port 162 is fully closed and the full pressure of the operating fluid is exerted on the piston 140 thereby compressing the spring 142 and causing the rapid vibration of the lever 118 to be transmitted through the link 112 to the piston 106 which in turn is reciprocated in the cylinder 140 at a rapid rate. This reciprocating movement of the piston 106 is transmitted through the body of liquid which fills the space above the piston 106, the pressure hose 100 and the space beneath the piston 80, to the piston 80 which is accordingly vibrated at the same rapid rate and caused to strike the shoe rest member 88 a rapid series of hammer blows. As the movement of the valve member 158 continues, the port 148 is eventually closed thereby and the admission of fluid under pressure to the cylinder 114 ceases. Associated with the cylinder 114 is a ball relief valve 210 which opens to an exhaust passage 212 and this ball valve limits the pressure of the fluid in the cylinder 114 to a value somewhat lses than the pressure of the operating fluid in the conduit 52. Hence, when the supply of pressure fluid to this cylinder is shut off, in the above manner, at each vibration of the lever 118 there will be a slight loss of pressure through the valve 210. Accordingly, the hammer-like action of the piston 80 will soon terminate after the valve member 158 has been moved to the right far enough to close the port 148. However, if the operator wishes to initiate the hammer-like action of the piston 80 again, he can do so by moving the hand lever 202 to shift the valve plunger 192 to the left so as to admit fluid under pressure to the cylinder 114 through the ports 188, 154 and the conduits 152, 144 and this action will be continued until he releases the hand lever 202 and permits the spring 193 to return the valve member 192 to the position in which it is shown in Fig. 2.

Referring to Fig. 3 of the drawings, it will be noted that as the grippers 12, 12 are operated to exert a pull on the upper U, a frictional resistance will be set up between the upper and the curved portion of the last at two points, indicated by the reference characters x, x and also that this frictional resistance will increase in direct proportion to the intensity of the pull applied to the upper by the grippers. Therefore, the resultant pull on that portion of the upper which lies across the top of the last, indicated by the reference character y, will be equal to the difference between the gripper pull and this frictional resistance. Because of this condition, it may become impossible to exert on the upper seized by the grippers a pull of sufficient intensity to stretch the aforementioned part of the upper snugly down into contact with the last without causing the gripper to tear the upper. However, when the last is subjected to a rapid series of percussive impulses, or hammer blows, in the manner above described, the frictional resistance between the upper and the last at the points x, x seems to be practically eliminated, or at least very materially reduced, so that substantially the entire force of the pull exerted by the grippers is effective on that portion of the upper which lies across the top of the last. Accordingly, the upper may be stretched snugly around and down into contact with the 'last without subjecting it to an excessive amount of pull. Under most operating conditions the relatively short period of action of the hammer which is provided during the movement of the valve member 158, which period may be lengthened or shortened by suitable adjustment of the needle valve 182, will be sufficient to give the desired results. However, should conditions require, an additional percussive action may be provided by the operator by means of suitable manipulation of the hand lever 202.

It Will be understood that the action of the hammer member 80 occurs during the initial stage of the operating cycle of the machine, being initiated in response to the operation of the toe gripper 10 by fluid under pressure admitted to the cylinder 38 through the conduit 52, and that the machine comes to a stop with the grippers exerting their respective pulls on the upper. It is during this dwell or inspection period that the operator adjusts the upper relatively to the last and, if he should not be satisfied that the upper has been drawn down snugly against the last, he may subject the last to an additional period of hammer action by manipulating the hand lever 202, which may be continued until the desired snugness of the upper on the last has been obtained. When the machine is again started, the overlaying and fastener inserting devices are actuated and the grippers are opened to release the marginal portion of the upper in the usual manner. Near the end of the operating cycle of the machine, the conduit 52, and also the passage 69, are connected to exhaust to permit the grippers to be returned to their initial starting positions. When this occurs, the valve member 158 is moved to the left by the spring 160 to the position shown in Fig. 2, the operating fluid in the bore 157, pipe 146, hose 144 and the space in the bore 114 above the piston 140, now exhausting freely through the conduit 176 and check valve 184 to the conduit 52.

By eliminating, or materially reducing the frictional resistance between the last and the upper materials, as a result of imparting to the last a rapid series of percussive impulses or hammer blows while the upper is subject to the pull of the grippers, in the manner which has been described above, the effectiveness of the pull applied by the grippers to shape the upper and to draw it snugly onto the last is greatly increased. Thus it is possible to obtain satisfactory results with the grippers exerting much less pull than otherwise would be required. This not only reduces the power needed to operate the machine but also avoids possible damage to the upper materials by subjecting them to excessive stress. Moreover, the upper materials seem to shape and to set themselves much better to the last and more permanently to assume the shape of the last as a result of the hammer 7 blows, or percussive impulses imparted thereto during the pulling of the upper by the grippers. This action is especially evident where, as is the case with the illustrated machine, the grippers, because of the manner in which they are operated by fluid under pressure, exerts a substantially unyielding pull on the upper materials. However, this same effect is still obtained where the grippers are operated mechanically through springs to exert a yielding pull on the upper materials.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert a pull on the upper tending to stretch the upper over the last, and means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers.

2. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, and means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers.

3. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, fluid pressure operated means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause said grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, and means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers.

4. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in ditferent locations around the peripheral edge or" the bottom of the shoe, a support for engaging the bot tom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert a pull on the upper tending to stretch the upper over the last, and means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percus sive impulses to the last during the operation of said grippers.

5. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, and means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers.

6. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, fluid pressure operated means for etfecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, and means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers.

7. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert a pull on the upper tending to stretch the upper over the last, means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, and control means operable in response to the application of pull by said grippers for initiating the action of said percussive impulse imparting means and for terminating such action after a variably predetermined interval.

8. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause said grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, and control means operable in response to the application of pull by said grippers for initiating the action of said percussive impulse imparting means and for terminating such action after a variably predetermined interval.

9. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, fluid pressure operated means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause said grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, and control means operable in response to the application of pull by said grippers for initiating the action of said percussive impulse imparting means and for terminating such action after a variably predetermined interval.

10. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert a pull on the upper tending to stretch the upper over the last, means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, and control means operable in response to the application of pull by said grippers for initiating the action of said fluid operated piston and for terminating such action after a variably predetermined interval.

11. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, and control means operable in response to the application of pull by said grippers for initiating the action of said fluid operated piston and for terminating such action after a variably predetermined interval.

12. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, fluid pressure operated means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, and control means operable in response to the application of pull by said grippers for initiating the action of said fluid operated piston and for terminating such action after a variably predetermined interval.

13. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in ditferent locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert a pull on the upper tending to stretch the upper over the last, means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, control means operable in response to the application of pull by said grippers for initiating the action of said percussive impulse imparting means and for terminating such action after a variably predetermined interval, and additional manually operable control means for initiating and terminating the action of said percussive impulse imparting means during the operation of said grippers.

14. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in difierent locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause said grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, control means operable in response to the application of pull by said grippers for initiating the action of said percussive impulse imparting means and for terminating such action after a variably predetermined interval, and additional manually operable control means for initiating and terminating the action of said percussive impulse imparting means during the operation of said grippers.

15. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, fluid pressure operated means for etfecting movement of said grippers in directions extending heightwise of a shoe on the support to cause said grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, control means operable in response to the application of pull by said grippers for initiating the action of said percussive impulse imparting means and for terminating such action after a variably predetermined interval, and additional manually operable control means for initiating and terminating the action of said percussive impulse imparting means during the operation of said grippers.

16. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in diflerent locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert a pull on the upper tending to stretch the upper over the last, means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, control means operable in response to'the application of pull by said grippers for initiating the action of said fluid operated piston and for terminating such action after a variably predetermined interval, and additional manually operable control means for initiating and terminating the action of said fluid operated piston during the operation of said grippers.

17. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in diflerent locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, control means operable in response to the application of pull by said grippers for initiating the action of said fluid operated piston and for terminating such action after a variably predetermined interval, and additional manually operable control means for initiating and terminating the action of said fluid operated piston during the operation of said grippers.

18. In a machine for shaping uppers over lasts, grippers for seizing marginal portions of the upper of a shoe on a last in different locations around the peripheral edge of the bottom of the shoe, a support for engaging the bottom of the shoe, fluid pressure operated means for effecting movement of said grippers in directions extending heightwise of a shoe on the support to cause the grippers to exert an unyielding pull on the upper tending to stretch the upper over the last, means including a fluid operated piston movable relatively to said shoe support for imparting a rapid series of percussive impulses to the last during the operation of said grippers, control means operable in response to the application of pull by said grippers for initiating the action of said fluid operated piston and for terminating such action after a variably predetermined interval, and additional manually operable control means for initiating and terminating the action of said fluid operated piston during the operation of said grippers.

References Cited in the file of this patent UNITED STATES PATENTS 

